The
utility is a program designed to simplify the maintenance of other programs.
Its input is a list of specifications
describing dependency relationships between the generation of
files and programs.
First of all, the initial list of specifications will be read
from the system makefile,
sys.mk
unless inhibited with the
-r
option.
The standard
sys.mk
as shipped with
Fx also handles
make.conf5,
the default path to which
can be altered via the
variable
__MAKE_CONF
Then the first of
BSDmakefile
makefile
and
Makefile
that can be found in the current directory, object directory (see
.OBJDIR )
or search path (see the
-I
option)
will be read for the main list of dependency specifications.
A different makefile or list of them can be supplied via the
-f
option(s).
Finally, if the file
.depend
can be found in any of the aforesaid locations, it will also be read (see
mkdep(1)).
When
searches for a makefile, its name takes precedence over its location.
For instance,
BSDmakefile
in the object directory will be favored over
Makefile
in the current directory.
The options are as follows:
-A
Make archive errors non-fatal, causing
to just skip the remainder
or all of the archive and continue after printing a message.
-B
Try to be backwards compatible by executing a single shell per command and
by executing the commands to make the sources of a dependency line in sequence.
This is turned on by default unless
-j
is used.
-C directory
Change to
directory
before reading the makefiles or doing anything else.
If multiple
-C
options are specified, each is interpreted relative to the previous one:
-C / -C etc
is equivalent to
-C /etc
-D variable
Define
variable
to be 1, in the global context.
-d flags
Turn on debugging, and specify which portions of
are to print debugging information.
Argument
flags
is one or more of the following:
A
Print all possible debugging information;
equivalent to specifying all of the debugging flags.
a
Print debugging information about archive searching and caching.
c
Print debugging information about conditional evaluation.
d
Print debugging information about directory searching and caching.
f
Print debugging information about the execution of for loops.
g1
Print the input graph before making anything.
g2
Print the input graph after making everything, or before exiting
on error.
j
Print debugging information about running multiple shells.
l
Print commands in Makefiles regardless of whether or not they are prefixed
by @ or other "quiet" flags.
Also known as "loud" behavior.
m
Print debugging information about making targets, including modification
dates.
s
Print debugging information about suffix-transformation rules.
t
Print debugging information about target list maintenance.
v
Print debugging information about variable assignment.
-E variable
Specify a variable whose environment value (if any) will override
macro assignments within makefiles.
-e
Specify that environment values override macro assignments within
makefiles for all variables.
-f makefile
Specify a makefile to read instead of the default one.
If
makefile
is not an absolute pathname,
will search for it as described above.
#include <case> makefile
is
`-
'
standard input is read.
Multiple
-f
options can be supplied,
and the makefiles will be read in that order.
Unlike the other command-line options,
-f
is neither stored in
.MAKEFLAGS
nor pushed down to sub-makes via
MAKEFLAGS
See below for more details on these variables.
-I directory
Specify a directory in which to search for makefiles and included makefiles.
Multiple
-I
options can be specified to form a search path.
The system makefile directory (or directories, see the
-m
option) is automatically appended at the tail of this path.
-i
Ignore non-zero exit of shell commands in the makefile.
Equivalent to specifying
`-
'
before each command line in the makefile.
-j max_jobs
Specify the maximum number of jobs that
may have running at any one time.
Turns compatibility mode off, unless the
-B
flag is also specified.
-k
Continue processing after errors are encountered, but only on those targets
that do not depend on the target whose creation caused the error.
-m directory
Specify a directory in which to search for
the system makefile and makefiles included via the <...> style.
Multiple
-m
options can be specified to form a search path.
This path will override the default system include path,
/usr/share/mk
The system include path will always be appended to the search path used
for "..."-style inclusions and makefile searches (see the
-I
option).
-n
Display the commands that would have been executed, but do not actually
execute them.
-P
Collate the output of a given job and display it only when the job finishes,
instead of mixing the output of parallel jobs together.
This option has no effect unless
-j
is used too.
-q
Do not execute any commands, but exit 0 if the specified targets are
up-to-date and 1, otherwise.
-r
Do not process the system makefile.
-S
Stop processing when an error is encountered.
Default behaviour.
This is needed to negate the
-k
option during recursive builds.
-s
Do not echo any commands as they are executed.
Equivalent to specifying
`@
'
before each command line in the makefile.
-t
Rather than re-building a target as specified in the makefile, create it
or update its modification time to make it appear up-to-date.
-V variable
Print
's
idea of the value of
variable
in the global context.
Do not build any targets.
Multiple instances of this option may be specified;
the variables will be printed one per line,
with a blank line for each null or undefined variable.
-v
Be extra verbose.
For multi-job makes, this will cause file banners to be generated.
-X
When using the
-V
option to print the values of variables,
do not recursively expand the values.
variable = value
Set the value of the variable
variable
to
value
-x warning_options
Specify extended warning options.
This option may be specified several times.
A
warning_option
can be prefixed with
``no
''
in which case the warning is switched off.
The currently available options are:
dirsyntax
Warn if anything except blanks and comments follows an
.endif
or
.else
directive.
See also the
.WARN
special target.
There are seven different types of lines in a makefile: file dependency
specifications, shell commands, variable assignments, include statements,
conditional directives, for loops, and comments.
In general, lines may be continued from one line to the next by ending
them with a backslash
(`\'
)
The trailing newline character and initial whitespace on the following
line are compressed into a single space.
FILE DEPENDENCY SPECIFICATIONS
Dependency lines consist of one or more targets, an operator, and zero
or more sources.
This creates a relationship where the targets
``depend''
on the sources
and are usually created from them.
The exact relationship between the target and the source is determined
by the operator that separates them.
The three operators are as follows:
:
A target is considered out-of-date if its modification time is less than
those of any of its sources.
Sources for a target accumulate over dependency lines when this operator
is used.
The target is removed if
is interrupted.
!
Targets are always re-created, but not until all sources have been
examined and re-created as necessary.
Sources for a target accumulate over dependency lines when this operator
is used.
The target is removed if
is interrupted.
::
If no sources are specified, the target is always re-created.
Otherwise, a target is considered out-of-date if any of its sources has
been modified more recently than the target.
Sources for a target do not accumulate over dependency lines when this
operator is used.
The target will not be removed if
is interrupted.
Targets and sources may contain the shell wildcard expressions
`?'
,
`*'
,
`[]'
and
`{}'
The expressions
`?'
,
`*'
and
`[]'
may only be used as part of the final
component of the target or source, and must be used to describe existing
files.
The expression
`{}'
need not necessarily be used to describe existing files.
Expansion is in directory order, not alphabetically as done in the shell.
SHELL COMMANDS
Each target may have associated with it a series of shell commands, normally
used to create the target.
Each of the commands in this script
must
be preceded by a tab.
While any target may appear on a dependency line, only one of these
dependencies may be followed by a creation script, unless the
`::
'
operator is used.
If the first characters of the command line are
`@
'
`-
'
and/or
`+
'
the command is treated specially.
A
`@
'
causes the command not to be echoed before it is executed.
A
`-
'
causes any non-zero exit status of the command line to be ignored.
A
`+
'
causes the command to be executed even if
-n
is specified on the command line.
VARIABLE ASSIGNMENTS
Variables in
are much like variables in the shell, and, by tradition,
consist of all upper-case letters.
The five operators that can be used to assign values to variables are as
follows:
=
Assign the value to the variable.
Any previous value is overridden.
+=
Append the value to the current value of the variable.
?=
Assign the value to the variable if it is not already defined.
:=
Assign with expansion, i.e., expand the value before assigning it
to the variable.
Normally, expansion is not done until the variable is referenced.
!=
Expand the value and pass it to the shell for execution and assign
the result to the variable.
Any newlines in the result are replaced with spaces.
Any whitespace before the assigned
value
is removed; if the value is being appended, a single space is inserted
between the previous contents of the variable and the appended value.
Variables are expanded by surrounding the variable name with either
curly braces
(`{}'
)
or parentheses
(`()'
)
and preceding it with
a dollar sign
(`$'
)
If the variable name contains only a single letter, the surrounding
braces or parentheses are not required.
This shorter form is not recommended.
Variable substitution occurs at two distinct times, depending on where
the variable is being used.
Variables in dependency lines are expanded as the line is read.
Variables in shell commands are expanded when the shell command is
executed.
The four different classes of variables (in order of increasing precedence)
are:
Environment variables
Variables defined as part of
's
environment.
Global variables
Variables defined in the makefile or in included makefiles.
Command line variables
Variables defined as part of the command line and variables
obtained from the
MAKEFLAGS
environment variable or the
.MAKEFLAGS
target.
Local variables
Variables that are defined specific to a certain target.
If the name of an environment variable appears in a makefile
on the left-hand side of an assignment,
a global variable with the same name is created, and the latter
shadows the former as per their relative precedences.
The environment is not changed in this case, and the change
is not exported to programs executed by
.
However, a command-line variable actually replaces
the environment variable of the same name if the latter exists,
which is visible to child programs.
There are seven local variables in
:
.ALLSRC
The list of all sources for this target; also known as
`>
'
.ARCHIVE
The name of the archive file; also known as
`!
'
.IMPSRC
The name/path of the source from which the target is to be transformed
(the
``implied''
source); also known as
`<
'
.MEMBER
The name of the archive member; also known as
`%
'
.OODATE
The list of sources for this target that were deemed out-of-date; also
known as
`?
'
.PREFIX
The file prefix of the file, containing only the file portion, no suffix
or preceding directory components; also known as
`*
'
.TARGET
The name of the target; also known as
`@
'
The shorter forms
`@
'
`!
'
`<
'
`%
'
`?
'
`>
'
and
`*
'
are permitted for backward
compatibility and are not recommended.
The six variables
`@F
'
`@D
'
`<F
'
`<D
'
`*F
'
and
`*D
'
are
permitted for compatibility with
AT&T System
V
makefiles and are not recommended.
Four of the local variables may be used in sources on dependency lines
because they expand to the proper value for each target on the line.
These variables are
.TARGET.PREFIX.ARCHIVE
and
.MEMBER
In addition,
sets or knows about the following internal variables or environment
variables:
$
A single dollar sign
`$'
,
i.e.
`$$'
expands to a single dollar
sign.
MAKE
The name that
was executed with
(argv [0]
)
.CURDIR
A path to the directory where
was executed.
The
utility sets
.CURDIR
to the canonical path given by
getcwd(3).
.OBJDIR
A path to the directory where the targets are built.
At startup,
searches for an alternate directory to place target files.
It will attempt to change into this special directory
and will search this directory for makefiles
not found in the current directory.
The following directories are tried in order:
${MAKEOBJDIRPREFIX}/`pwd`
${MAKEOBJDIR}
obj.${MACHINE}
obj
/usr/obj/`pwd`
The first directory that
successfully changes into is used.
If either
MAKEOBJDIRPREFIX
or
MAKEOBJDIR
is set in the environment but
is unable to change into the corresponding directory,
then the current directory is used
without checking the remainder of the list.
If they are undefined and
is unable to change into any of the remaining three directories,
then the current directory is used.
Note, that
MAKEOBJDIRPREFIX
and
MAKEOBJDIR
must be environment variables and should not be set on
's
command line.
The
utility sets
.OBJDIR
to the canonical path given by
getcwd(3).
.MAKEFILE_LIST
As
reads various makefiles, including the default files and any
obtained from the command line and
.include
and
.sinclude
directives, their names will be automatically appended to the
.MAKEFILE_LIST
variable.
They are added right before
begins to parse them, so that the name of the current makefile is the
last word in this variable.
MAKEFLAGS
The environment variable
MAKEFLAGS
may initially contain anything that
may be specified on
's
command line,
including
-f
option(s).
After processing, its contents are stored in the
.MAKEFLAGS
global variable, although any
-f
options are omitted.
Then all options and variable assignments specified on
's
command line, except for
-f
are appended to the
.MAKEFLAGS
variable.
Whenever
executes a program, it sets
MAKEFLAGS
in the program's environment to the current value of the
.MAKEFLAGS
global variable.
Thus, if
MAKEFLAGS
in
's
environment contains any
-f
options, they will not be pushed down to child programs automatically.
The
utility effectively filters out
-f
options from the environment and command line although it
passes the rest of its options down to sub-makes via
MAKEFLAGS
by default.
When passing macro definitions and flag arguments in the
MAKEFLAGS
environment variable,
space and tab characters are quoted by preceding them with a backslash.
When reading the
MAKEFLAGS
variable from the environment,
all sequences of a backslash and one of space or tab
are replaced just with their second character
without causing a word break.
Any other occurrences of a backslash are retained.
Groups of unquoted space, tab and newline characters cause word
breaking.
.MAKEFLAGS
Initially, this global variable contains
's
current run-time options from the environment
and command line as described above, under
MAKEFLAGS
By modifying the contents of the
.MAKEFLAGS
global variable, the makefile can alter the contents of the
MAKEFLAGS
environment variable made available for all programs which
executes.
This includes adding
-f
option(s).
The current value of
.MAKEFLAGS
is just copied verbatim to
MAKEFLAGS
in the environment of child programs.
Note that any options entered to
.MAKEFLAGS
neither affect the current instance of
nor show up in its own copy of
MAKEFLAGS
instantly.
However, they do show up in the
MAKEFLAGS
environment variable of programs executed by
.
On the other hand, a direct assignment to
MAKEFLAGS
neither affects the current instance of
nor is passed down to
's
children.
Compare with the
.MAKEFLAGS
special target below.
MFLAGS
This variable is provided for backward compatibility and
contains all the options from the
MAKEFLAGS
environment variable plus any options specified on
's
command line.
.TARGETS
List of targets
is currently building.
.INCLUDES
See
.INCLUDES
special target.
.LIBS
See
.LIBS
special target.
MACHINE
Name of the machine architecture
is running on, obtained from the
MACHINE
environment variable, or through
uname(3)
if not defined.
MACHINE_ARCH
Name of the machine architecture
was compiled for, defined at compilation time.
VPATH
Makefiles may assign a colon-delimited list of directories to
VPATH
These directories will be searched for source files by
after it has finished parsing all input makefiles.
Variable expansion may be modified to select or modify each word of the
variable (where a
``word''
is whitespace-delimited sequence of characters).
The general format of a variable expansion is as follows:
{variable[:modifier[:...]]}
Each modifier begins with a colon and one of the following
special characters.
The colon may be escaped with a backslash
(`\'
)
C / pattern
/ replacement/ [1g
]
Modify each word of the value,
substituting every match of the extended regular expression
pattern
(see
re_format7)
with the
ed(1)Ns-style
replacement
string.
Normally, the first occurrence of the pattern in
each word of the value is changed.
The
`1'
modifier causes the substitution to apply to at most one word; the
`g'
modifier causes the substitution to apply to as many instances of the
search pattern as occur in the word or words it is found in.
Note that
`1'
and
`g'
are orthogonal; the former specifies whether multiple words are
potentially affected, the latter whether multiple substitutions can
potentially occur within each affected word.
E
Replaces each word in the variable with its suffix.
H
Replaces each word in the variable with everything but the last component.
L
Converts variable to lower-case letters.
M pattern
Select only those words that match the rest of the modifier.
The standard shell wildcard characters
( `*'
`?'
,
and
`[]'
)
may
be used.
The wildcard characters may be escaped with a backslash
(`\'
)
N pattern
This is identical to
M
but selects all words which do not match
the rest of the modifier.
O
Order every word in the variable alphabetically.
Q
Quotes every shell meta-character in the variable, so that it can be passed
safely through recursive invocations of
.
R
Replaces each word in the variable with everything but its suffix.
S / old_string
/ new_string/ [g
]
Modify the first occurrence of
old_string
in each word of the variable's value, replacing it with
new_string
If a
`g'
is appended to the last slash of the pattern, all occurrences
in each word are replaced.
If
old_string
begins with a caret
(`^'
)
old_string
is anchored at the beginning of each word.
If
old_string
ends with a dollar sign
(`$'
)
it is anchored at the end of each word.
Inside
new_string
an ampersand
(`&'
)
is replaced by
old_string
Any character may be used as a delimiter for the parts of the modifier
string.
The anchoring, ampersand, and delimiter characters may be escaped with a
backslash
(`\'
)
Variable expansion occurs in the normal fashion inside both
old_string
and
new_string
with the single exception that a backslash is used to prevent the expansion
of a dollar sign
(`$'
)
not a preceding dollar sign as is usual.
old_string=new_string
This is the
AT&T System
V
style variable substitution.
It must be the last modifier specified.
If
old_string
or
new_string
do not contain the pattern matching character
%
then it is assumed that they are
anchored at the end of each word, so only suffixes or entire
words may be replaced.
Otherwise
%
is the substring of
old_string
to be replaced in
new_string
T
Replaces each word in the variable with its last component.
Directives, conditionals, and for loops reminiscent
of the C programming language are provided in
.
All such structures are identified by a line beginning with a single
dot
(`.'
)
character.
The following directives are supported:
.include <file>
.include file
Include the specified makefile.
Variables between the angle brackets
or double quotes are expanded to form the file name.
If angle brackets
are used, the included makefile is expected to be in the system
makefile directory.
If double quotes are used, the including
makefile's directory and any directories specified using the
-I
option are searched before the system
makefile directory.
.sinclude <file>
.sinclude file
Like
.include
but silently ignored if the file cannot be found and opened.
.undef variable
Un-define the specified global variable.
Only global variables may be un-defined.
.error message
Terminate processing of the makefile immediately.
The filename of the
makefile, the line on which the error was encountered and the specified
message are printed to the standard error output and
terminates with exit code 1.
Variables in the message are expanded.
.warning message
Emit a warning message.
The filename of the makefile,
the line on which the warning was encountered,
and the specified message are printed to the standard error output.
Variables in the message are expanded.
Conditionals are used to determine which parts of the Makefile
to process.
They are used similarly to the conditionals supported
by the C pre-processor.
The following conditionals are supported:
.if
[! expression
]
[operator expression ...
]
Test the value of an expression.
.ifdef
[! variable
]
[operator variable ...
]
Test the value of a variable.
.ifndef
[! variable
]
[operator variable ...
]
Test the value of a variable.
.ifmake
[! target
]
[operator target ...
]
Test the target being built.
.ifnmake
[! target
]
[operator target ...
]
Test the target being built.
.else
Reverse the sense of the last conditional.
.elif
[! expression
]
[operator expression ...
]
A combination of
.else
followed by
.if
.elifdef
[! variable
]
[operator variable ...
]
A combination of
.else
followed by
.ifdef
.elifndef
[! variable
]
[operator variable ...
]
A combination of
.else
followed by
.ifndef
.elifmake
[! target
]
[operator target ...
]
A combination of
.else
followed by
.ifmake
.elifnmake
[! target
]
[operator target ...
]
A combination of
.else
followed by
.ifnmake
.endif
End the body of the conditional.
The
operator
may be any one of the following:
||
logical
OR
&&
Logical
AND
of higher precedence than
`||
'
As in C,
will only evaluate a conditional as far as is necessary to determine
its value.
Parentheses may be used to change the order of evaluation.
The boolean operator
`!
'
may be used to logically negate an entire
conditional.
It is of higher precedence than
`&&
'
The value of
expression
may be any of the following:
defined
Takes a variable name as an argument and evaluates to true if the variable
has been defined.
make
Takes a target name as an argument and evaluates to true if the target
was specified as part of
's
command line or was declared the default target (either implicitly or
explicitly, see
.MAIN
before the line containing the conditional.
empty
Takes a variable, with possible modifiers, and evaluates to true if
the expansion of the variable would result in an empty string.
exists
Takes a file name as an argument and evaluates to true if the file exists.
The file is searched for on the system search path (see
.PATH )
target
Takes a target name as an argument and evaluates to true if the target
has been defined.
An
expression
may also be an arithmetic or string comparison, with the left-hand side
being a variable expansion.
Variable expansion is
performed on both sides of the comparison, after which the integral
values are compared.
A value is interpreted as hexadecimal if it is
preceded by 0x, otherwise it is decimal; octal numbers are not supported.
The standard C relational operators are all supported.
If after
variable expansion, either the left or right hand side of a
`==
'
or
`!=
'
operator is not an integral value, then
string comparison is performed between the expanded
variables.
If no relational operator is given, it is assumed that the expanded
variable is being compared against 0.
When
is evaluating one of these conditional expressions, and it encounters
a word it does not recognize, either the
``make''
or
``defined''
expression is applied to it, depending on the form of the conditional.
If the form is
.if.ifdef
or
.ifndef
the
``defined''
expression is applied.
Similarly, if the form is
.ifmake
or
.ifnmake
the
``make''
expression is applied.
If the conditional evaluates to true the parsing of the makefile continues
as before.
If it evaluates to false, the following lines are skipped.
In both cases this continues until a
.else
or
.endif
is found.
For loops are typically used to apply a set of rules to a list of files.
The syntax of a for loop is:
.for variable in expression
<make-rules>
.endfor
After the for
expression
is evaluated, it is split into words.
The
iteration
variable
is successively set to each word, and substituted in the
make-rules
inside the body of the for loop.
COMMENTS
Comments begin with a hash
(`#'
)
character, anywhere but in a shell
command line, and continue to the end of the line.
SPECIAL SOURCES
.IGNORE
Ignore any errors from the commands associated with this target, exactly
as if they all were preceded by a dash
(`-'
)
.MAKE
Execute the commands associated with this target even if the
-n
or
-t
options were specified.
Normally used to mark recursive
's
.NOTMAIN
Normally
selects the first target it encounters as the default target to be built
if no target was specified.
This source prevents this target from being selected.
.OPTIONAL
If a target is marked with this attribute and
cannot figure out how to create it, it will ignore this fact and assume
the file is not needed or already exists.
.PRECIOUS
When
is interrupted, it removes any partially made targets.
This source prevents the target from being removed.
.SILENT
Do not echo any of the commands associated with this target, exactly
as if they all were preceded by an at sign
(`@'
)
.USE
Turn the target into
's
version of a macro.
When the target is used as a source for another target, the other target
acquires the commands, sources, and attributes (except for
.USE
of the
source.
If the target already has commands, the
.USE
target's commands are appended
to them.
.WAIT
If special
.WAIT
source appears in a dependency line, the sources that precede it are
made before the sources that succeed it in the line.
Loops are not being
detected and targets that form loops will be silently ignored.
SPECIAL TARGETS
Special targets may not be included with other targets, i.e., they must be
the only target specified.
.BEGIN
Any command lines attached to this target are executed before anything
else is done.
.DEFAULT
This is sort of a
.USE
rule for any target (that was used only as a
source) that
cannot figure out any other way to create.
Only the shell script is used.
The
.IMPSRC
variable of a target that inherits
.DEFAULT 's
commands is set
to the target's own name.
.END
Any command lines attached to this target are executed after everything
else is done.
.IGNORE
Mark each of the sources with the
.IGNORE
attribute.
If no sources are specified, this is the equivalent of specifying the
-i
option.
.INCLUDES
A list of suffixes that indicate files that can be included in a source
file.
The suffix must have already been declared with
.SUFFIXES
any suffix so declared will have the directories on its search path (see
.PATH
placed in the
.INCLUDES
special variable, each preceded by a
-I
flag.
.INTERRUPT
If
is interrupted, the commands for this target will be executed.
.LIBS
This does for libraries what
.INCLUDES
does for include files, except that the flag used is
-L
.MAIN
If no target is specified when
is invoked, this target will be built.
This is always set, either
explicitly, or implicitly when
selects the default target, to give the user a way to refer to the default
target on the command line.
.MAKEFILEDEPS
Enable the
``Remaking Makefiles''
functionality, as explained in the
Sx REMAKING MAKEFILES
section below.
.MAKEFLAGS
This target provides a way to specify flags for
when the makefile is used.
The flags are as if typed to the shell, though the
-f
option will have
no effect.
Flags (except for
-f
and variable assignments specified as the source
for this target are also appended to the
.MAKEFLAGS
internal variable.
Please note the difference between this target and the
.MAKEFLAGS
internal variable: specifying an option or variable
assignment as the source for this target will affect
both
the current makefile and all processes that
executes.
.MFLAGS
Same as above, for backward compatibility.
.NOTPARALLEL
Disable parallel mode.
.NO_PARALLEL
Same as above, for compatibility with other
pmake
variants.
.ORDER
The named targets are made in sequence.
.PATH
The sources are directories which are to be searched for files not
found in the current directory.
If no sources are specified, any previously specified directories are
deleted.
Where possible, use of
.PATH
is preferred over use of the
VPATH
variable.
.PATHsuffix
The sources are directories which are to be searched for suffixed files
not found in the current directory.
The
utility
first searches the suffixed search path, before reverting to the default
path if the file is not found there.
This form is required for
.LIBS
and
.INCLUDES
to work.
.PHONY
Apply the
.PHONY
attribute to any specified sources.
Targets with this attribute are always
considered to be out of date.
.POSIX
Adjust
Ap s
behavior to match the applicable
POSIX
specifications.
(Note this disables the
``Remaking Makefiles''
feature.)
.PRECIOUS
Apply the
.PRECIOUS
attribute to any specified sources.
If no sources are specified, the
.PRECIOUS
attribute is applied to every
target in the file.
.SHELL
Select another shell.
The sources of this target have the format
key = value
The
key
is one of:
path
Specify the path to the new shell.
name
Specify the name of the new shell.
This may be either one of the three builtin shells (see below) or any
other name.
quiet
Specify the shell command to turn echoing off.
echo
Specify the shell command to turn echoing on.
filter
Usually shells print the echo off command before turning echoing off.
This is the exact string that will be printed by the shell and is used
to filter the shell output to remove the echo off command.
echoFlag
The shell option that turns echoing on.
errFlag
The shell option to turn on error checking.
If error checking is on, the shell should exit if a command returns
a non-zero status.
hasErrCtl
True if the shell has error control.
check
If
hasErrCtl
is true then this is the shell command to turn error checking on.
If
hasErrCtl
is false then this is a command template to echo commands for which error
checking is disabled.
The template must contain a
`%s'
ignore
If
hasErrCtl
is true, this is the shell command to turn error checking off.
If
hasErrCtl
is false, this is a command template to execute a command so that errors
are ignored.
The template must contain a
`%s'
meta
This is a string of meta characters of the shell.
builtins
This is a string holding all the shell's builtin commands separated by blanks.
The
meta
and
builtins
strings are used in compat mode.
When a command line contains neither a meta
character nor starts with a shell builtin, it is executed directly without
invoking a shell.
When one of these strings (or both) is empty all commands are executed
through a shell.
unsetenv
If true, remove the
ENV
environment variable before executing any command.
This is useful for the Korn-shell
(ksh
)
Values that are strings must be surrounded by double quotes.
Boolean values are specified as
`T'
or
`Y'
(in either case) to mean true.
Any other value is taken to mean false.
There are several uses of the
.SHELL
target:
Selecting one of the builtin shells.
This is done by just specifying the name of the shell with the
name
keyword.
It is also possible to modify the parameters of the builtin shell by just
specifying other keywords (except for
path )
Using another executable for one of the builtin shells.
This is done by specifying the path to the executable with the
path
keyword.
If the last component is the same as the name of the builtin shell, no
name needs to be specified; if it is different, the name must be given:
.SHELL: path="/usr/local/bin/sh"
selects the builtin shell
``sh
''
but will execute it from
/usr/local/bin/sh
Like in the previous case, it is possible to modify parameters of the builtin
shell by just specifying them.
Using an entirely different shell.
This is done by specifying all keywords.
The builtin shells are
``sh
''
``csh
''
and
``ksh
''
Because
Fx has no
ksh
in
/bin
it is unwise to specify
name = Qq ksh
without also specifying a path.
.SILENT
Apply the
.SILENT
attribute to any specified sources.
If no sources are specified, the
.SILENT
attribute is applied to every
command in the file.
.SUFFIXES
Each source specifies a suffix to
.
If no sources are specified, any previous specified suffices are deleted.
.WARN
Each source specifies a warning flag as previously described for the
-x
command line option.
Warning flags specified on the command line take precedence over flags
specified in the makefile.
Also, command line warning flags are pushed to sub-makes through the
MAKEFLAGS
environment variables so that a warning flag specified on the command
line will influence all sub-makes.
Several flags can be specified on a single
.WARN
target by seperating them with blanks.
REMAKING MAKEFILES
If the special target
.MAKEFILEDEPS
exists in the Makefile,
enables the
``Remaking Makefiles''
feature.
After reading Makefile and all the files that are included using
.include
or
.sinclude
directives (source Makefiles)
considers each source Makefile as a target and tries to rebuild it.
Both explicit and implicit rules are checked and all source Makefiles
are updated if necessary. If any of the source Makefiles were rebuilt,
restarts from clean state.
To prevent infinite loops the following source Makefile targets are ignored:
::
targets that have no prerequisites but have commands
!
targets
targets that have
.PHONY
or
.EXEC
attributes
targets without prerequisites and without commands
When remaking a source Makefile options
-t
(touch target),
-q
(query mode), and
-n
(no exec) do not take effect, unless source Makefile is specified
explicitly as a target in
command line.
Additionally, system makefiles and
.depend
are not considered as Makefiles that can be rebuilt.
ENVIRONMENT
The
utility uses the following environment variables, if they exist:
MACHINEMAKEMAKEFLAGSMAKEOBJDIR
and
MAKEOBJDIRPREFIX
FILES
.depend
list of dependencies
Makefile
list of dependencies
makefile
list of dependencies
obj
object directory
sys.mk
system makefile
/usr/share/mk
default system makefile directory
/usr/share/doc/psd/12.make
PMake tutorial
/usr/obj
default
MAKEOBJDIRPREFIX
directory.
/etc/make.conf
default path to
make.conf5
EXAMPLES
List all included makefiles in order visited:
"make -V .MAKEFILE_LIST | tr \ \\n"
COMPATIBILITY
Older versions of
used
MAKE
instead of
MAKEFLAGS
This was removed for
POSIX
compatibility.
The internal variable
MAKE
is set to the same value as
.MAKE
support for this may be removed in the future.
Most of the more esoteric features of
should probably be avoided for greater compatibility.
The determination of
.OBJDIR
is contorted to the point of absurdity.
In the presence of several
.MAIN
special targets,
silently ignores all but the first.
.TARGETS
is not set to the default target when
is invoked without a target name and no
.MAIN
special target exists.
The evaluation of
expression
in a test is very simple-minded.
Currently, the only form that works is
`.if'
${VAR} op something
For instance, you should write tests as
`.if'
${VAR} == string
not the other way around, which would give you an error.
For loops are expanded before tests, so a fragment such as:
The parsing code is broken with respect to handling a semicolon
after a colon, so a fragment like this will fail:
HDRS= foo.h bar.h
all:
.for h in ${HDRS:S;^;${.CURDIR}/;}
...
.endfor
A trailing backslash in a variable value defined on the command line causes
the delimiting space in the
MAKEFLAGS
environment variable to be preceded by that backslash.
That causes a submake to not treat that space as a word delimiter.
Fixing this requires a larger rewrite of the code handling command line
macros and assignments to
.MAKEFLAGS